src/base/pepper_file_util.h

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#ifndef MOZC_BASE_PEPPER_FILE_UTIL_H_
#define MOZC_BASE_PEPPER_FILE_UTIL_H_

#include <string>

#include "base/port.h"

namespace pp {
class Instance;
}  // namespace pp

namespace mozc {

class Mmap;

// Interface for Papper File system.
class PepperFileSystemInterface {
 public:
  virtual ~PepperFileSystemInterface() {}
  virtual bool Open(pp::Instance *instance, int64 expected_size) = 0;
  virtual bool FileExists(const string &filename) = 0;
  virtual bool DirectoryExists(const string &dirname) = 0;
  virtual bool ReadBinaryFile(const string &filename, string *buffer) = 0;
  virtual bool WriteBinaryFile(const string &filename,
                               const string &buffer) = 0;
  virtual bool DeleteFile(const string &filename) = 0;
  virtual bool RenameFile(const string &from, const string &to) = 0;
  virtual bool RegisterMmap(Mmap *mmap) = 0;
  virtual bool UnRegisterMmap(Mmap *mmap) = 0;
  virtual bool SyncMmapToFile() = 0;
};

// Utility class for Pepper FileIO.
// This class can't be used in the NaCl main thread.
// The Pepper FileIO APIs must be called in the NaCl main thread, and they are
// asynchronous. So the methods of PepperFileUtil calls Pepper FileIO APIs in
// the NaCl main thread using pp::Core::CallOnMainThread() and waits the result
// using mozc::UnnamedEvent.
class PepperFileUtil {
 public:
  // Initializes PepperFileUtil.
  static bool Initialize(pp::Instance *instance, int64 expected_size);

  // Sets mock for unit testing.
  static void SetPepperFileSystemInterfaceForTest(
      PepperFileSystemInterface *mock_interface);

  // Returns true if a file or a directory with the name exists.
  static bool FileExists(const string &filename);

  // Returns true if the directory exists.
  static bool DirectoryExists(const string &dirname);

  // Reads a file and returns ture.
  // If the file does not exist or an error occurs returns false.
  static bool ReadBinaryFile(const string &filename, string *buffer);

  // Writes a file and returns ture.
  // If an error occurs returns false.
  static bool WriteBinaryFile(const string &filename, const string &buffer);

  // Deletes a file and returns ture.
  // If an error occurs returns false.
  static bool DeleteFile(const string &filename);

  // Renames a file.
  // This method first deletes the "to" file if it exists, and tries to rename.
  static bool RenameFile(const string &from, const string &to);

  // Registers Mmap object.
  static bool RegisterMmap(Mmap *mmap);

  // Unegisters Mmap object.
  static bool UnRegisterMmap(Mmap *mmap);

  // Call SyncToFile() method of the all registered Mmap objects.
  static bool SyncMmapToFile();
};

}  // namespace mozc

#endif  // MOZC_BASE_PEPPER_FILE_UTIL_H_